Method for automatic production and transportation of flaskless sand moulds in metal casting

ABSTRACT

In a method for producing and conveying horizontally divided flaskless sand molds, the molding sand is pneumatically introduced into mold frame cavities formed above and below a laterally moving match plate having a pattern on both sides and terminated by vertically moving mold frames and vertically moving press dies cooperating with said mold frames. The molding sand is pressed by a corresponding relative movement between said press dies and match plate, after which the match plate is separated from the mold halves by a corresponding relative movement between the press dies and the mold frame on one hand, and the match plate on the other. The match plate is then moved laterally into its rest position and the mold is closed, if necessary, after the insertion of cores. The finished closed mold rests on the bottom press die which is substantially flush with the upper edge of the lower mold frame, and is then displaced laterally from the molding position by the match plate as it returns from its rest position. The ejected finished mold is added to a mold train, and the finished mold is at least supported on two sides by supporting means.

United States Patent [72] Inventor Eugen Buhler Weg zur Walk 96,Burtenbach, Kreis, Germany [21] Appl. No, 753,640

[22] Filed Aug. 19, 1968 [45] Patented Jan. 19, 1971 [32] Priority Aug.18, 1967, Apr. 27, 1968 [33] Germany [31] 1,583,526 and 1,758,245

[54} METHOD FOR AUTOMATIC PRODUCTION AND TRANSPORTATION OF FLASKLESSSAND 3,273,207 9/ l 966 Taccone l64/29X 3,293,703 12/1966 Taccone164/160 FOREIGN PATENTS 603,754 8/1960 Canada 164/40 912,608 12/1962Great Britain 164/180 Primary Examiner-J. Spencer Overholser AssistantExaminer-JOhn E. Roethel Attorney-Holman, Glascock, Downing and SeeboldABSTRACT: [n a method for producing and conveying horizontally dividedflaskless sand molds, the molding sand is pneumatically introduced intomold frame cavities formed above and below a laterally moving matchplate having a pattern on both sides and terminated by vertically movingmold frames and vertically moving press dies cooperating with said moldframes. The molding sand is pressed by a corresponding relative movementbetween said press dies and match plate, after which the match plate isseparated from the mold halves by a corresponding relative movement:between the press dies and the mold frame on one hand, and the matchplate on the other. The match plate is then moved laterally into itsrest position and the mold is closed, if necessary, after the insertionof cores. The finished closed mold rests on the bottom press die whichis substantially flush with the upper edge of the lower mold frame, andis then displaced laterally from the molding position by the match plateas it returns from its rest position. The ejected finished mold is addedto a mold train, and the finished mold is at least supported on twosides by supporting means.

PATENTEEDJA'MQIB?! T f 3636196 sum 111G513 V IN V EN TOR.

PATENIEU JANIQIQI I Sum 020F11- FIG 4 FIG. 2

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PATENIEDJAMQIQII sum 13m 13 INVENTOR.

The invention concerns a method and an apparatus for the automaticmechanical production as well as for the conveyance of horizontallydivided fiaskless sand molds.

In the two us. Pat. Nos. 1,291.996and 1.091 .020 are already describedmachines, operated rhythmically by apressuremedium, for-theproduction offlask less horizontally divided sand molds, whichhave two mold framesarranged The object of the present invention is, o"n the one hand, to

achieve a fully automatic operation in the production of horizontallydivided molds and a larger castings thereby avoidabove and below ahorizontal plate-that can. be swung out in a horizontal plane, movedvertically, and which cooperates with vertically moving press dies. v aa These known mold-making machines permit the semiautomatic productionor flaskle'ss horizontally divided casting molds, but they have thedisadvantage that the 'molding'sand must be manually placednin the moldframes; that the finished ntolds can only be conveyed on base plates;and furthermore that the finishedmolds must be covered with so-calledjackets before theyare-moved away inorder to be able to withstandthepressure of theliquidmetal during casting. The liftingof the finishedmolds from the mold nakingmachine, the'pla'cement of the latteron aconveyor device and the placing of the jackets over the finished moldsmustbe effected byhand. The H great'amount of manual work involved inthe known methods ing base plates and jackets, and on the other hand, tomake such an automatic process economical by rapid pattern changes,notonly for the production of large runs. but also for 'the productionof small runs or single pieces as well as for small castings.

The present invention relates to a method for the mechanical productionas well as for the conveyance of horizontally divided flaskless sandmolds, where the molding sand is pneumatically introduced into two moldframe cavities formed above and below a laterally moving match platehaving a pattern on both sides and terminated by vertically moving moldframes and vertically moving press dies cooperating with said frames Themolding sand is pressed by a corresponding relacause loss of timeandhighwage costs andprecludes the'effit n w of automatic procedures.Furthermore. the supply of-a great number of base plates and jacketsrequires high investment costs. 3 Y

in cen ral Pat.- No. l 950,560 is described a chute mechanism by meansof which the lowermold frame and'then the upper mold 'frame'can becharged by machines of the above deseribed 'type with molding sand. U.S.Pat. No.'

3,229,366Ydescribes a mold-making machine of the above horizontal inmolding position which can be swung'out into a vertical plane,' wherethe molding sand is pneumatically has the disadvantage that because of'thes'uccessive filling of the lowerupper mold frame there is still aloss of time.

.tive movement between these press dies and the match plate,

afterwhich the match plate is separated fromthe mold halves by acorresponding relative movement between the press 'dies and the moldframe on the one hand, and the match plate, on the other hand. The matchplate is then moved laterally into its rest position and the mold isclosed, if necessary, after the insertion of cores. after which thefinished mold is exposed by relative movement between at least one pressdie and the two mold frames, tobe moved away. Such a method ischaracterized according to the invention by the fact that the finishedmold resting after its ejection on the bottom die, which is subthe matchplate from its rest position and is introduced as a newly added part toa. mold train moving past the finished molds are supported on at leasttwo 'sides by supporting i mentioned type. but with a pattern plate(match plate) The second method'has the disadvantagethat the moldingsand blasted into the interior of the? mold frames mixes withthecornpressed ai'r'conveying it and the pattern halves are damaged bytheresulting erosive action ofthesand blower,

and also difficulties are "encountered in eliminating the entrained air.Both of the last mentioned methods have the same disadvantages as theabove described methods, namely that the finished mold must betransferred from the mold making machine to the conveyor device by hand.and they require base plates and jackets. The Swiss. Pat. No. productionof vertically divided flaskless sand molds where the molding sand isintroduced by blasting into a cavity formed between two vertical matchplate halves and is sub sequently pressed'by moving the two match platehalves and swinging away one match plate half from the finished moldbody, thelatter beingpushed by horizontal movement of the 364,078describes a plant for the means.

By the term mold train" is to be understood a series of individualfinished molds which directly touch each other with their unreinforcedend faces, or a series of finished molds that are supported on all foursides by supporting means and whose respective adjoining end facesupportingmeans touch each other. t 1

qThe invention also relatesto a plant for carrying out the methodaccording to the invention with a sand mold-making machine operatedcyclically by a pressure medium, with mold frames moving verticallyabove and below a laterally moving match plate, which is horizontal inmolding position, and

.cooperating with respective vertically moving press dies, as well aswith a device for the supply of molding sand to the mold frame cavities.Such a plant is characterized according to the invention by the factthat a preferably plate-shaped sliding die for the ejection of thefinishedmolds is arranged on I one side of the match plate moving in ahorizontal direction,

] the invention is preferablydesigned as a hollow body and has othermatch plate half onto a horizontal conveyor track where a it joins as anewly added'part of mold train moving toward a casting pit. This knownmethod has the advantage of being completely automatic, butbecauseof the"vertical divisionofthe mold,'there are difficulties regarding theinsertion of the core and the production'oflarger castings, since thefinishedmold bodies cannot'withstand high internal pressure because theyare not supported in any way. I

All the above described known methods have the disadvantage that thechange of the patterns is cumbersome and timeconsuming. and the knownsemiautomatic methods are therefore uneconomical in the production of asmaller series of castings.

and that a conveyor track for the mold train receiving the finishedmolds and passing by a castingpit is arranged laterally of themoldmaking machine in the direction of motion of the sliding die and ina plane which the press surface of the bottom die assumes in itsdirection of ejection of the finished mold, the finished molds beingsupported at least on two lateral sur faces by supporting means beingadvanced along this conveyor track.

The match plate of the mold-making machine according to on its upper andlower plate-surface a plurality of apertures,

preferably uniformly distributed over the respective plate surface, intowhich can be introduced corresponding holding and/or fixing means forexch angeable patterns. In a match plate designed as a hollow body, thecavity of the match plate can be connected according to another featureof the inven- .tion over corresponding controllable switching elementsselectively to a vacuum or pressure gas source. The match plate can havea plate frame into which upper and lower dividing plates can beinserted.

Above and below the guide section of the mold-making machine determiningthe departing position of the match plate can be preferably arranged,according to another feature of the invention, swing-away infraredradiators for heating the match plates.

The supporting means for the finished mold have according to theinvention the form of clamping plates, guided along the conveyor trackfor the mold train and preferably provided with adhesive tips andcooperating in pairs, which can be tipped about a horizontal axis. Theclamping plates are preferably arranged in known weight irons, guidedabove the conveyor track for the mold train. that they are opened upautomatically during their change. According to a preferred embodimentof the invention, a number of supporting units are provided which havetwo or four clamping plates opposing cach'other in pairs and serving asa support for the respective finished mold, these clamping plates beingarticulated by means protruding beyond this weight plate beingarticulated on cross guide rods, preferably self-locking in the mannerof toggle levers, whose respective other ends are in turn articulated ona weight connected with a trolley head and moving along a vertical guidesecuredwith its bottom end on the weight plate and having a stop at thetop. This movement is such that in case the rollers of the trolley headrest on a longitudinal guide extending over the conveyor track of themold train, the weight plate is held in a position detached from the topsurface of the finished mold and the clamping plates in a spreadposition exceeding the respective horizontal dimension of the finishedmolds. When the trolley is released downward, the weight plate is placedon the respective top surface of the finished mold and the clampingplates are thus pressed against the respective lateral faces of thefinished mold.

The feeding power necessary for feeding the mold train is preferablyderived, according to the invention, by the mutual end faced bearing ofthe supporting means for the respective finished molds from a powersource which effects, on the one hand, the lateral ejection of the lastfinished mold from the molding machine, and on the other hand, by actingon the respective supporting means of the second last ejected finishedmold to advance of the entire finished mold train by one finished moldlength.

The arrangement for the pneumatic filling of molding sand into the moldframe cavities of the mold making machine has, according to theinvention, a gas compressor, a pressure gas tank, and a molding sandtank filled by a filling device from the molding sand bunker andarranged laterally of the mold making machine. Preferably two pressuregas lines are located between the pressure gas tank and the molding sandtank for admitting pressure gas over one or two controlled valves. Ifnecessary a vacuum tank and a vacuum line can be connected with theinterior of the match plates and provided with at least one controlvalve. Furthermore, an upper and lower molding sandline associated withthe upper end lower mold frame cavity is included.

In an embodiment of the plant according to the invention the two moldingsand lines are arranged laterally in known manner in such a way thatthey are in communication with the respective mold frame cavitiesthrough lateral slots in the mold frames of the molding machine whenthese frames are in filling position. In a preferred embodiment of theplant according to the invention, the two molding sand lines areconnected to the upper and lower sand chambers of the moldmakingmachine, which in turn are in communication with the mold frame cavitiesthrough openings of the two press dies. The sand chambers of the moldmaking machine can have each an upper and lower telescopic extensionwhose interior is in communication through openings of the respectiveplateshaped press die with the respective adjoining mold frame cavities.According to a preferred embodiment of the invention, the two moldingsand lines, a connecting line connecting these sand lines with eachother, and the upper and lower sand chamber of the mold-making machineare combined in the vertical plane to a C-shaped sand tank forming themold making machine frame, which has at the top the filling deviceconnected with the sand bunker and one of the two pressure gas nipples,also at its two leg ends the two sand chambers with the respective pressdies, furthermore in its horizontal center plane the match plate guide,and on the lower arc of the C the other pressure gas line nipple.

In order to accelerate the production of the casting molds and thepouring of the finished mold trains, several conveyor tracks for thefinished mold trains. which can be displaced transverse to theirlongitudinal-axes relative to the mold-making machine, can bealternatively used.

Other features and advantages of the invention will result from thefollowing specification of some embodiments with reference to theattached drawings, in which:

FIG. 1 shows a partial section of a schematic elevation of oneembodiment of the mold-making machine for sand mold production andconveyor plant according to the invention;

FIGS. 2 to 6 show a simplified schematic lateral elevation, similar toFIG. I, which represents the machine corresponding to its operationsuccessively in pressing position, in lifting position, incore-inserting position, in mold-closing position and in mold ejectingposition;

FIG. 7 shows a schematic elevation of the mold-making machine as well asof the respective conveyor track for the finished mold train of themold-production and conveyor plant during the ejection of a finishedmold, turned by 90 about the vertical axis of the machine as compared toFIGS. 1 to 6;

FIG. 8 shows a schematic cross section through the conveyor track forthe mold train of the plant according to the invention with thesupporting means according to the invention for supporting the sidewallsof the finished molds;

FIG. 9 shows a partial section of a schematic top view of a match plate,preferably to be used in combination with the plant according to theinvention, a so-called "top plate" being inserted in the left half ofthe drawing;

FIG. 10 represents a section along the plane X-X in FIG. 9, seen in thedirection of the arrows, which shows that in addition a so-called bottomplate" is inserted in the left halfof the lustrated in FIGS. 9 to 12with the attached inlet, pattern, and

a pattern unit according to the invention in the production ofa moldhalf;

FIG. 14 shows a schematic side view in the direction of the arrow XIV inFIG. 9, in which the top and bottom part of the match plate is shown ina partly folded state;

FIG. 15 shows a schematic perspective view of a preferred I embodimentof the match plate according to the invention used in combination with amold-making machine according to the invention;

FIG. 16 shows a schematic partial side view of another embodiment of thesand mold production and conveyor plant according to the invention;

FIG. 17 shows a partial section of a top view of the plant representedin FIG. 16;

FIG. 18 shows a partial section along the plant XVIII-XVIII in FIG. 17-,

FIG. 19 shows a partial top view of the plant represented in FIG. I6seen in the direction of the arrow XIX in FIG. 16;

FIG. 20 shows a schematic section along the plane XXXX in FIG. 16, seenin the direction of the arrows;

FIG. 21 shows a schematic partial vertical-longitudinal section througha modified embodiment of the mold frame and press die arrangement of amold making machine according to the invention; and

FIGS. 22 to 26 shows respectively partial verticaI-longitu dinalsections through the mold-making machine of the sand mold production andconveyor plant represented in FIGS. 16 to 20 in various operatingposition.

FIRST EMBODIMENT With references toFIGS. 1 to 8 of the drawings anembodiment of asand mold production and conveyor plant according to theinvention will now be described. M w

FIG. 1 shows a part of the mold-making and conveyor plant according tothe invention showing the foundationframe of the mold-making machineaccording to jthe invention with cross yoke A. ln'this foundation frameis held for vertical displacement a top die'Ba, which is fixed, forexample, in this embodiment of the invention during the working cycle ofthe machine. This top die can be set at different levels for theproduction of patterns of different profile heightby'means o fahydraulic drive Fa, so that the workingstrokes' of the machine and theirtime intervals are kept as short as possible. An upper mold fram'e'Ca.is vertically displaceable with respect to top die Ba by means of ahydraulic drive Eaf A double-sided match plate D is at the beginning ofthe working cycle of the machine in the position represented in' FIG. Iof'the drawings, in which the molding'sand is introduced pneumaticallyinto.

terposed match plate D. In this state the molding sand is introducedpneumatically by means of :the' device N.-This is the basic first stepfor the pressing process.

FIG. 2 shows the position of the mold frames Ca and Cb after thepressing. In the compression of the molding sand. the bottom die Bb hasmoved'upward relative to the lower mold .frame Cb, which is heldsomewhat by a certain initial stress of the hydraulic drives Ea, Eb andhas thus been protected from uncontrolled sliding down..for' example, byits own weight. The bottom die Bb haslifted the'match plate D from itsrails and taken it upwards together. with'th'e upper mold frame Carelative to thestop die Ba, so that the molding sand contained themachine. The bottoindie Bb of the machine can be moved I verticallyj up'andd own 'in known manner .by means of a hydraulic drive Fb. Aflowerframe Cb is vertically displaceable relative'to Eb. n I, l p v p FIG. 7of the drawings shows an ejectiori de'vice G for the this bottom die Bbby means'of a hydraulic drive match plate'D of the niachine'in aschematic representation.

the machine the bottom moldframe together with the bottom die Bb canpass during the pressing ope'rationthrough the frame-shaped truck"lifting the ina'tch plate D upwards and pressingitagainst the top'dieBa. t i

F IGS .7 and ,8 of the drawings alsoshow the con veyor belt I of themold-making plant according to the invention forming the conveyor trackof the mold train, on which ejected finished molds are arranged. Theedges, of the horizontal separating joints of these flaskless sand moldshave, according.

to the invention, complementaryibeveis L, which serve to fix the upperand lowermold halves during the feeding'p'rocesses. They have beenomitted for clarityssake" in FIGS. 1 to 7, in the latter in the matchplate. w V

FIG. 8 shows a schematicYcross section through the conveyor belt l andalso supporting means according tothe invention for the lateral supportof the finished molds resting on the conveyor belt. These have, forexample, the form of clamping plates M, as mentioned above, which arepressed by means of a controllable linkage, according to the invention,laterally against the finished molds sothat the latter can withstand thecasting pressure deformation force resulting from the feeding process.These clamping plates M can also be actuated, if this seems advisable,from the top, for'example by using known weightirons as it is shown ontheright of FIG. 8. 1

FIG. I of the drawings also shows the pneumatic filling device N for themolding sand of the moldmaking plant according to theinvention. Themolding sand is accelerated during the filling process simultaneouslywith air from the, top and from the side. In this way a uniform fillingof both mold frames I Ca and Cb is achieved. Louvered diaphragms 0ensure the proper air flow. v t

- FIRST EMBODIMENT OPERATION The individual working cycles of themold-making plant ac- FIGS. 1 to 7 of the drawings. l t

' FIG. 1 shows the first working stage. Here the upper mold frame Ca andthe lower mold frame Cb are applied to the in impulse, slightly trailingbehind the inserting movement of the match plate, is imparted to theconveyor belt, the power of the in the upper mold frame has also beencompressed. A slight jbackpressure can be exerted by means of the upperhydraulic match plate D is again placed on its frame-shapedtruck or, if

it is designed itself as a truck, on the rails and is subsequentlymovedto the rear by means of the horizontally acting hydraulic driveindicatedat G in FIG. 7 of the drawings. In'case the match plate Disdesigned itself as a truck, a hook-shaped vertically detachableconnection is provided between this hydraulic drive and the match plateD, likewise indicated in FIG.'7 (not numbered),

The removal of the match plate D results in the core-inserting positio'nrepresented in FIG. 4. Cores can be inserted either by hand or by ,meansof a :special core-inserting mechanism. Subsequently the bottom die Bbwith the lower mold frame Cb and the lower mold half moves up untilitbears on the upper mold half, the two mold frames Ca and Cb beingsimultaneously pulled back or subsequently pulled back by means of thehydraulic drives Ba and Eb so that they release the entire mold. w

1 The mold is thus closed and'rests in the position shown in FIG. 5 onthe bottom die Bb. In its following downward move ment it is disengagedfrom the top die. I

' Y The bottom die subsequently moves so that it is aligned wit theconveyor belt I. This position represented in FIG. 6. t

If the-match plate D and its framesshaped truck are inis the ejectionposition troduced again by means of the hydraulic drive G, the finishedmold K is ejected at the same time onto the conveyor belt I as shown'inFIG. 7.

The'two'mold frames Ca and Cb are subsequently raised and lowered againby means of their hydraulic drives Ea and Eb until they bear again'onthe match plate D, the starting position according to FIG. I has beenreached again and the working cycle can start anew.

The finished molds form, as shown in FIG. 7, a closed mold train havingtwo abutting surfaces each of the four lateral surfaces of the finishedmolds supporting one another. The contact pressure of the molds, whichis equal to the ejection power and the driving force required fornondriven conveyor belt must be limited so that overstress of the moldswhich might result in lateral destruction is avoided. To this end, the

conveyor belt I can be driven or supplemented, for example by means of astepping mechanism, whose activity is preferably started by overpressureof the pre sure medium actuating the hydraulic drive G.

The arrangement can be such that .a synchronous motionalinsertingmovement of the match plate ,being so limited that I cording tothe invention will now be described on the basis of destruction of thefinished molds' is avoided. The driving power of the conveyor belt ispreferably obtained from a power source producing power in excess of theintroduction of the match plate. a

The support of the exposed other two sides of the molds is effected, asmentioned above, by clamping plates. These run in synchronism with theconveyor belt I. They can be secured by a linkage on the belt or theycan be articulated on weight irons guided at the top, or they can besecured on a separate belt, which can follow, for example, by frictioncontact.

The control of the working cycle of the mold making plant according tothe invention can be effected in a simple manner, for example, by limitswitches over control pistons by means of a pressure medium. The thrustsof the various hydraulic drives, for example of the hydraulic drives Ba,Bb, Fa, Pb and G, can be limited by known means, for example, overflowvalves.

The height and area of the molds can be increased by correspondingdimensioning of the parts of the plant, for example, of the mold frames,press-dies, conveyor belt etc. up to orders of magnitude which werepossible so far only in automatic plants with mold flasks.

The double-sided support of the finished molds advancing on the conveyorbelt I can be effected in a modification of the invention, instead of bythe above described clamping plates, by conveyor belts arranged at bothsides of the finished mold train and extending parallel to the conveyorbelt 1, whose bank surfaces are vertical. Such supporting conveyor beltscan be either driven or nondriven. They can be covered, if necessary,with spur plates extending perpendicularly to the conveyor beltsurfaces, which reach between the individual finished molds and supporttheir end faces.

Both the conveyor belt I and the above mentioned supporting conveyorbelts can be'supported to such an extent by closely arranged guiderollers that they lay practically in a plane surface. They can have, forexample, the form of endless steel belts.

The clamping plates used according to the invention preferably forsupporting the finished mold train on both sides can be made tiltableabout axes parallel to the direction of conveyance in the embodiment ofthe invention described here, and their respective degrees of tilting orpressing against the outer walls of the finishing mold train can becontrolled, for example, by a cam track extending parallel to theconveyor belt.

Instead of a single conveyor belt 1, several conveyor belts can also beused which can be displaced transverse to the direction of conveyanceand which can cooperate selectively with the mold making machineaccording to the invention.

The device according to the invention for the pneumatic feeding of themolding sand into the two mold frame cavities has preferably the form ofa rotatably or fixedly mounted box or drum-shaped tank in which arearranged louvered air baffles, and in which the molding sand isaccelerated by compressed air introduced simultaneously both from thetop and from the side.

As it can be seen from FIGS. 1 to 6 of the drawings, the hydraulicdrives effecting the vertical displacement of the two mold frames arearranged parallel to the hydraulic drives effecting the verticaldisplacement of the two press dies. As it will be described below, aconcentric arrangement of the hydraulic drives for the press dies andthe mold frames can also be provided instead of the parallelarrangement.

MATCH PLATE The match plate 4 and the truck carrying the match plate inthe ejection position of the machine can have on the side facing theconveyor belt I, a sliding die, for example, in the form of an easilymoving articulated vertical surface, which bears during the ejection ofthe finished mold on the vertical outer mold surface facing it.

With reference to FIGS. to of the drawings, the detail of a match plateaccording to the invention will now be described, which can be used incombination with the above described sand mold production and conveyorplants according to the invention represented in FIGS. 1 to 9, and alsowith other embodiments of such a plant, as will be described more fullybelow.

The preferred embodiment of a match plate according to the invention,represented schematically in FIGS. 9 to 14, has

a plate frame which consists of a main frame part I and two upper andlower frame parts 1' and 1 respectively articulated thereon. The top andbottom edges of the main frame part 1 of the match plate and therespective surfaces of the upper match plate frame part I and of thelower main frame part I" bearing thereon are so ground that the tightmutual bearing of these match plate frame parts shown in FIGS. 10, l1and 12 of the drawings is ensured. On one side of the main frame part Iof the match plate frame are secured, for example, four slightly elasticholding angles 2 which are pushed toward each other by their slightspring effect in the direction of the arrows P indicated in FIG. 10. Atthe free ends of these holding angles 2 are secured axle pieces 3 whosesalient free ends, on both sides, are designed as axle journals 3a. Ononeside each of the top and bottom part 1 and 1" respectively of thematch plate frame are secured, for example, two rigid hinge arms 4 whichform an integral part with meshing gear wheels 4a in whose hub bores aresupported the axle journals 3Z1 of the axle pieces 3. The dimensions ofthe parts are such that, when the top part 1 of the match plate frameand the bottom part 1" of the match plate frame are turned so that theybear on the two ground surfaces of the main part of the match plateframe, the holding angles 2 on both sides are elastically bent againstthe directions indicated by the arrows P, so that they tend to press thetop part 1' and the bottom part I of the match plate frame against therespective bearing surfaces of the main part I of the match'plate frame.On the other hand, the elastic holding angles 2 have a tendency, whentop part 1' and bottom part 1" of the match plate frame are folded awayfrom the main part 1 of the match plate frame, to press the looselymeshing gear wheels 40 into a tight mutual engagement to make sure thatthe movements of the top part 1' and of the bottom part 1" of the matchplate frame are specially synchronized to ensure a complete weightbalance in favor of a low energy expenditure for moving these parts. Onthe sides opposite the sides of the top plate 1' and of the bottom plateI" of the match plate frame holding the respective hinge arms 4 arelikewise secured limited elastic clamping parts 5 whose free ends areprovided with bearing bores 5a in which are sup ported thejournal-shaped free ends 6a of clamping pieces 6, which in turn can bepressed together by means of a clamping screw 7. This clamping screw 7passes, on the one hand. through a continuous bore of one clamping piece6, and on the other hand, is arranged in a slot-shaped recess 6b of theother clamping piece so that it can be moved away to disengage theclamping connection. By tightening the clamping screw 7, a tight mutualbearing of the associated bearing surfaces of the main part 1 of thematch plate frame, on the one hand, and of the top and bottom plate 1'and 1" respectively of the match plate frame, on the other hand, can beachieved.

The match plate is divided in the embodiment represented and describedhere by a central holding bar 8, 8' and 8" respectively into two halvesso that the top and bottom side of the match plate according to theinvention receiving the pattern change are each divided into two parts.Such a subdivision is naturally not compulsory and can be omitted byeliminating the holding bars 8, 8, 8". On the other hand, a furthersubdivision of the top and bottom sides of the match plate according tothe invention by additional holding bars, not shown, in longitudinal andtransverse directions is also possible within the framework of theinvention. The holding bars 8, 8', 8" are preferably detachably mountedon the frame parts I, l and 1" of the match plate according to theinvention in a manner not shown in the drawing. The top and bottomplates 1 and 1" respectively of the match plate frame and the top andbottom parts 8' and 8" respectively of the holding bars are providedwith corresponding shoulders or ledgeshaped projections on which rest aso-called top plate" 9 and a so-called bottom plate 9", which areconnected by detachable fastening means, not shown in the drawings, withthe top part 1 and the bottom part 1" respectively of the match plateframe. The top whichjare indicated in FIGS. 9an'd ll) of the drawings by-brokenlines. a

.-n the insides of the main part l of the match plate frame as well ason the holding bars 8, if any can be provided shoulders and holdingstrips respectively and 8a, which serve as a supportfor innerreinforcing plates 10. which, just like the holding bars 8. servetoincrease the resistance of the match plate according to the inventionagainst external pressure. The shoulder and holding" strips la and 80also have the function, for reasonsto be discussed later,-of serving asa packing support for relief plates, if relief patterns must be moldedwith the a match plate according to the invention. a I Q On one orseveral of the outer four sides of the main 'part 1 each other in theform of'a square raster, as'it can be seen from FIG. 9. The changepattern halves to be secured on the top plate 9 and on the bottom plate9" are preferably "provided in known manner with'cylindricalfitting pins12a (FIG. 13 which can bejntroduced intothe fastening apertures 12'. Thefastening of the change pattern halves on the top plate 9', and bottomplate 9 can be effected with screws, threaded bolts, clamping bolts,clamp. clips or byimagnetic force, in

which latter case the top, plate 9' and the bottom plate 9" must be madeof corresponding magnetic material. Apart 4 from thefpossiblemagneticfastening of the change pattern halves, however, the top plate 9 andthebottom plate 9'' ean also be made of a different material, forexample,of wood or of plastic. 4 a

; The fastening apertures l2'can be numbered continuously,

' asjit canbe seen from H0. 9. Accordingto the invention, an radditional trialplate can be 'provided in this case, which is notrepresented in th'edrawings, whose top and bottom-surfaces,

plate 9 and bottom plate 9" I respectively are the carriers-of thechangepattern halveswith flaskless sand mold making machines, the feeding ofthe molding sand by means of compressed air into the mold frame and thusleads not only to a marked'acceleration of the feeding process, but alsohelps substantially to reduce or eliminate completely the difficultiesencountered normally in these leases when molding complicated patterns.It is readily understandable that during the evacuation of the interiorof the match plate according to the invention the elimination of the.compressed air necessary for filling the molding sand into the moldframe is effected through the uncovered fastening apertures 12 of thetop plate 9' and bottom plate 9" and that it is detachment of thefinished mold from the pattern is greatly facilitated, since thecompressed air issuing from the interior of the match plate through theapertureslZ not covered by the pattern provides an air cushion below andabove the two mold halves to be removed which and removal. 5 r v v:In'order to be able to limit the passage of air through the fasteningapertures l2 of the topplate 9 and of the bottom plate 9" during thefilling of the molding sand and during the detachment of the finishedmold halves, it is possible according to the invention to'insert' knownnozzle plugs 12b (FIG. l3),into the fastening apertures 12 notrequiredfor fastening and fixing the change-pattern halves which permitsonly a limited passage of air through these apertures. These nozzleplugsare preferably designed as slotted plugs whose slot width isselected so narrow that the entrance of molding sand particles'into thehollow of the match plate during the evacuation of this hollow isavoided.

Despite the above described advantages. the design of the facilitatestheir detachment match plate according to the invention as a hollow bodyis not likewiseprovided with numbered'apertures, are identical in theirdimensions, size, arrangement and numbering of these apertures with thetop and bottom surfaces of the match plate accordingto the invention andwhich canbe" inscribed with wipe-off writing materials. Thismeasure-according-to the'invention permits experimenting during theoperation of the mold-making machine by means of the trial plate therespective optimum coveringof the pattern plate with the, respectivepatterns to be molded in the new series, and permits the marking of thefastening apertures necessary for fixing and fastening the patternhalves on the pattern plate. The. fastening of the pattern halves on thematch plate according to the invention can then be effected in a veryshort time by usingthe "it possible to-outline the change pattern'halfapplied onthe trial plate, for example, with a crayon, andthus todetermine a in a short time which fastening apertures are necessary forfastening and fixing the pattern halves on the match plate ac cording tothe invention. a a a a e a The fastening apertures 12 of the patternplate according to I the invention have another function, too,'however.As it can ble mounted on the match plate according to the invention.

This detachability of the top plate 9" and of the bottom plate 9" fromthe main part of the match plate is of particular importance, with agreat subdivision of the match -plate cover marked numbers of thenecessary fastening apertures. The inscribability ofthe top and bottomsurfaces of the trial plate according to the invention with wipe-offwriting materials makes surfaces by holding bars 8' and 8",when thematch plate is to be covered simultaneously. with different series ofdifi'erent patterns ordifierent quantities ln these cases the timenecessary for the pattern change by removing the respective top andbottom plate 9' and 9" and attaching another top and bottom platealready covered with the new pattern halves is substantially reduced.But where such cases do not appear, the fastening apertures 12 can beprovided readily directly in the upper and lower bottom of a solid orhollow match plate as continuous holes. This has the result that thedivision of the match plate frame of the match plate according to theinvention into a main part 1 and a top frame 1, as, well as a bottomframe part 1 is likewise not compulsory. This division, and particularlythe simultaneous possibility of tilting away from the top part 1' andthe bottom part 1'. of the match plate frame serve again merely toaccelerate the change of the patterns and particularly to make thehollow of the match plate according to the invention accessible, vivhichis of particular advantage when relief plates are to be molded. FIG. 14of the drawings shows the advantage of a weight-balance resulting fromthe symmetry of the folding away of the top plate 1" and of the to avacuum and/or compressed air-source. Such an evacuation possibility ofthe interior of the match plate according to the invention facilities,particularly when used in combination bottom plate 1" of the match plateframe according to the invention.

If the evacuation or pressurization of the hollow of the match plateaccording to the invention is considered and the match plate frame isdivided into a main frame part I and into a detachable and fold-away topframe part 1' and an identical bottom frame part 1'', it may beadvisable to provide on or in the proximity of the mutual contact edgesof these parts packing strips of suitable material, for example, ofrubber.

FIGS. 9 to 14 of the drawings shows that a so-called runner" 13 ispreferably detachably mounted on the top side of the top part I of thematch plate frame. As it can be seen, particularly from FIG. 13, therunner 13 cooperates with a sprue 13a arranged for elastic displacementon the top die as well as, if necessary, with one or morecorrespondingly arranged risers, which are likewise arranged in suitablemanner on the top die of the respective mold-making machine. Naturallyseveral runners can be provided at a suitable point instead ofa singlerunner 13. FIG. 13 shows on the right side next to runner 13, a gate 13battached on the top plate 9' by means of a fitting pin 12a, which isjoined by a pattern 13c, likewise fixed with fitting pins 120 on the topplate. The invention also concerns the idea of using in connection withsuch a runner 13 or with several such runners one-piece pattern units13d, which can likewise be seen in FIG. 13. These units consists, in thecase of the top side of the match plate, of a gate, if necessary afeeder with inlet and the respective pattern half, the gate adjoiningdirectly the respective runner 13. Due to such a measure according tothe invention, the time necessary for changing the patterns is likewisereduced to a minimum.

These pattern units 13d are made of cast iron, brass, aluminum, wood orplastic, and are one piece or composed of several parts by means of acommon holding strip. The units can consist of magnetic material, or canhave a magnetic or magnetizable holding shoe, if they are to be securedby magnetic force on to the match plate.

MATCH PLATE IN USE In connection with FIGS. 14 and 15 of the drawings,the application of the match plate according to the invention incombination with the mold-making machine according to the invention asillustrated in FIGS. 1 to 8 will be described. As indicated in FIG. 14the match plate 1 according to the invention rests on a slide frame 14(broken lines) which can be dis' placed along horizontal guide rails 15.In FIG. 15 of the drawings the range of action of the mold frame and ofthe press dies of the respective flaskless mold-making machine isindicated by an upper and lower mold frame 16 and 16" as represented bybroken lines. As it can be seen from FIG. 15, two match plates 1A and 1Bare arranged side by side in the slide frame 14. FIG. 15 showsfurthermore that the slide frame 14 can be moved back and forth in thedirection of arrow Q by means of a hydraulic drive (not shown in thedrawing) between a position in which the match plate 1A is in the rangeof action of the mold frame 16' and 16" of the mold-making machine, andthe represented position in which the match plate 1A is outside thisrange of action. According to the invention, the guide rails 15, whichare likewise represented in FIG. 15, forms a part of another slide frame17, which can be moved back and forth by means of a hydraulic drive,secured on the machine, along guide rails 19 transverse to the directionof arrow Q in the direction of the arrow R in such a way that, on theone hand, the match plate 1A can be brought in the represented positionof the slide frame 17 into the range of action of the mold frames 16'and 16" of the mold-making machine, and on the other hand, in anunrepresented position of the slide frame 17, the match plate 18 can bebrought into this range of action. Both slide frames 14 and 17 are sodesigned that the mold-making machine can cooperate unhindered with therespective match plate when the match plate 1A or 1B is in theabove-mentioned operative position.

The last described double match plate arrangement according to theinvention permits the pattern to be changed during the operation of themold-making machine on the respective match plate which is not inoperative position. while the other match plate moves in and out of therange of action in the working rhythm of the mold-making machine.Shutdown time for the change of the patterns is thus avoided.

With magnetic fastening of the pattern halves and pattern units on thematch plate, the arrangement of a second match plate may be unnecessaryunder certain circumstances, since the pattern change can then beeffected in a very short time in the extended state of the match duringthe operation of the machine.

In the arrangement described in connection with FIG. 15 of the drawings,it may be of advantage to arrange three or more match plates side byside on the slide frame 14, instead of only two, in which case the track19 of the slide frame 17 must naturally be so dimensioned that one ofthe match plates according to the invention can cooperate with themold-making machine, while a pattern change is effected on the othermatch plates during the operation of the molding making machines.

According to another feature of the invention, the slide frame 14 can beused as a sliding die for the ejection of the respective finished sandmolds from the mold-making machine.

It follows from the foregoing considerations that the match plateaccording to the invention in its various embodiments, or the matchplate arrangement according to the invention in its various embodiments,particularly in combination with flaskless sand mold-making machines,allows not only a considerable acceleration of the pattern change, butalso leads to an acceleration and trouble-free performance of themolding process proper. The match plate and match plate arrangementaccording to the invention particularly in combination with fiasklesssand mold-making machines, a substantial contribution to increasing theeconomy of fully automatic casting plants.

The above described match plate according to the invention can be usednot only in combination with mold-making machines of the type describedin this connection, but also generally in combination with semiautomaticor automatic mold-making machines. In this application too, it offersall the above-described advantages.

SECOND EMBODIMENT In connection with FIGS. 16 to 18 of the drawingsanother embodiment of a sand mold production-and-conveyor plantaccording to the invention will be described. As far as parts arerepresented in these FIGS. which are identical with the partsrepresented in FIGS. 1 to 15, they have been provided with the samereference letters or reference numbers.

FIG. 16 shows just like FIG. 7 a side view a mold-making machinegenerally designated with 101, with an adjoining conveyor track for thefinished molds, generally designated with 102.

The machine frame of the mold-making machine 101 is formed by themolding sand feeding device to be described later, particularly withreference to FIG. 18. The mold-making machine 101, like the mold-makingmachine described above with reference to FIGS. 1 to 7, has a top dieBa, a bottom die Bb, an upper mold frame Ca and a lower mold frame Cb.The vertical displacement of the lower mold frame Cb is effected by ahydraulic drive, identical with the hydraulic drive Ea (FIGS. 1 to 7),which is not represented for claritys sake in the drawings and whichacts in opposite direction to Eb. The vertical displacement of the topdie Ba is effected by means of a hydraulic drive Fa and that of thebottom die Bb by means of a hydraulic drive Fb acting in oppositedirection. Preferably in the horizontal center between the two hydraulicdrives Ea, Eb and Fa, Fb is fixedly mounted a horizontal guide 103 inwhich a match plate D designed as a truck is so guided that it canperform horizontal movements, but no vertical movements. The match plateD can have any of the forms described above in connection with FIGS. 9to 15 of the drawings.

In FIGS. 16 to 18 of the drawings, the mold-making machine 101 accordingto the invention is represented in an operating position in which thematch plate D is in molding position and in which the upper mold frameCa bears with its

1. A method producing and conveying horizontally divided flaskless sandmolds comprising: a. introducing a match plate between two mold framesand dies of a mold-making machine actuatable in a substantially verticaldirection; b. lowering the upper mold frame and raising the lower moldframe to abut against said match plate and thereby forming mold cavitieson each side of said match plate; c. pneumatically feeding molding sandinto said mold cavities; d. compressing said molding sand against saidmatch plate by moving said dies relative said mold frames; e. raisingand lowering said upper mold frame and die and said lower mold frame anddie respectively to free said match plate; f. moving said match platefrom said mold-making machine to a rest position which is laterallyadjacent thereto; g. moving at least one die relative to its mold frameto close said mold, the closed mold resting on said bottom die which issubstantially flush with the upper edge of said lower mold frame; h.returning said match plate from its rest position to said mold-makingmachine to laterally eject the finished closed mold and start anothermolding cycle; i. supporting said finished closed mold on at least twosides by supporting means, said supported finished closed mold adaptedto bear against previously made molds to form a mold train.
 2. A methodas claimed in claim 1 wherein said mold train is moved on conveyingmeans in the direction of a casting pit.
 3. A method as claimed in claim2 wherein said conveying means is a horizontal conveyor track, the solemotive force for said mold train being that of the returning match platewhich ejects said finished mold and thereby moves said mold train onemold length.
 4. A method as claimed in claim 3 wherein the adjacentfinished molds in the mold train have their lateral sides supported bysaid supporting means, the adjacent sides mutually bear on each other.5. A method as claimed in claim 2 wherein said conveying means is adriven conveyor track, and the driving power is derived from the samepower source as the driving power for said match plate movement.
 6. Amethod as claimed in claim 2 wherein said supporting means support thelateral sides of said finished molds in said mold train and adjacentsupporting means bear on one another to prevent undue pressure frombeing exerted on the mutually adjacent mold sides in said mold train,and the power source for the movement of said match plate and themovement of said mold train are the same.
 7. A method as claimed inclaim 6 wherein separate power sources actuate said match plate and saidmold train.
 8. A method as claimed in claim 1 comprising the furtherstep of changing the patterns on said match plate during the period saidmatch plate is in said rest position without interrupting the moldingcycle.
 9. A method as claimed in claim 1 comprising the further step ofheating said match plate while it is in said rest position by anexternal to the plate source.
 10. A method as claimed in claim 1 whereinsaid pneumatic feeding of molding sand to said upper and lower moldcavities is carried out in a substantially vertical direction.
 11. Amethod as claimed in claim 10 wherein said feeding to the upper andlower mold cavities is done simultaneously.
 12. A method as claimed inclaim 1 comprising the further steps of evacuating said match plateduring the feeding of said molding sand to augment such feeding intosaid mold cavities, and pressurizing said match plate during the raisingand lowering of said mold frames and dies to augment freeing saidfinished mold from said match plate.